1. Field of the Invention
The present invention relates to long rod penetrators and more particularly to composite long rod penetrators that have longitudinal hardness gradients.
2. Description of the Prior Art
Prior art long rod penetrators for defeating armored targets have consisted of metal matrix composite and monolithic designs. Development work on matrix composite long rod penetrators has been ongoing for a number of years. However, the work on composites as well as monolithic penetrators, reported by various investigators, has based the evaluation of the penetrator's materials on a misleading assumption. Investigators have been evaluating different materials to determine penetrator effectiveness based on the striking velocity required to defeat a target. Consequently, results of tests will show that the striking velocity limit for the composite and the monolithic penetrators are similar at each hardness. The problem with this evaluation procedure is that it doesn't take into consideration the effectiveness of these penetrators after they pass though a target. This characteristic is particularly important when evaluating penetrator effectiveness against multilayered targets. When the progress of the penetrators through various targets is considered, it can be shown that at the initial high velocities certain materials are better than others. Moreover, as the velocity of the penetrators is lost during progress through the targets, material with the best initial penetration is inferior at reduced velocity during later stages of progress. Consequently, long rod penetrators require a combination of unique properties in order to increase their effectiveness. This combination of properties is not found in present homogeneous monolithic or composite long rod penetrators.